The Code

                        
                            // get the text input from the page
                            function getValues() {

                                let message = document.getElementById('userInput').value;

                                if (message.length == 0) {
                                    Swal.fire ({
                                        icon: 'error',
                                        backdrop: false,
                                        title: 'Oops!',
                                        text: 'Please enter a message to check for a palindrome'
                                    });
                                } else {
                                    let isPalindrome = checkForPalindrome(message);

                                    displayResults(isPalindrome);
                                }
                            }

                            // reverse the message
                            function reverseMessage(userInput) { // if input = hello

                                let output = ''; // output = ['h', 'e', 'l', 'l', 'o']

                                for (let i = userInput.length-1; i >= 0; i--) {

                                    output += userInput[i]
                                }

                                return output;
                            }

                            function checkForPalindrome(input) {
                                let regex = /[^a-zA-Z0-9]/g;

                                input = input.replace(regex, '');
                                input = input.toLowerCase();

                                let reversed = reverseMessage(input)

                                if (reversed === input) {
                                    return true;
                                } else {
                                    return false;
                                }
                            }

                            // display the reverse message
                            function displayResults(isPalindrome) {
                                document.getElementById('alert').classList.remove('invisible', 'alert-danger', 'alert-success');

                                if (isPalindrome == true) {
                                    document.getElementById('msg').textContent = `Nice Job, that's a palindrome`;
                                    document.getElementById('alert').classList.add('alert-success');
                                } else {
                                    document.getElementById('msg').textContent = `Oh no, that's not a palindrome`;
                                    document.getElementById('alert').classList.add('alert-danger');
                                }
                            }